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Opioids

AH-7921

Street names: Legal heroin, Doxylam

AH-7921 — White/off-white powder or tablets; sold online as 'research chemical' around 2013–2015

What it does

  • Morphine-like opioid synthesized in the 1940s; ~80% of morphine's potency
  • Short history as a 'legal high' before scheduling

Key risks

  • Multiple UK deaths 2014–2015 (detected alongside etizolam and other NPS)
  • Standard opioid overdose profile
  • The case that ended the UK's 'legal high' tolerance — led directly to the PSA 2016

Overdose signs

  • Respiratory depression
  • Pinpoint pupils
  • Unresponsive

📋Quick facts

Also known asLegal heroin, Doxylam
CategoryOpioids
Schedule / classSchedule I (US, 2015); Class A UK
AppearanceWhite/off-white powder or tablets; sold online as 'research chemical' around 2013–2015
Street priceResidual; grey-market $20–$60/g
Legal statusSchedule I US; Class A UK; controlled everywhere listed
Last updated2026-09-18
Sources: EMCDDA, DEA, NIDA

Category comparison — Opioids

SubstanceClassTop risksStreet price
AH-7921Schedule IMultiple UK deaths 2014–2015 (detected alongside etizolam and other NPS); Standard opioid overdose profileResidual
U-47700 (Pink / U4)Schedule ILinked to multiple DEATHS before scheduling — the drug behind the 2016 'pink' overdose wave; Potency ~7× morphine~$20–$60/g grey-market
Street prices are regional estimates. Potency and cuts vary constantly.

?Frequently asked questions

What does AH-7921 look like?

White/off-white powder or tablets; sold online as 'research chemical' around 2013–2015

What are the signs of a AH-7921 overdose?

Respiratory depression; Pinpoint pupils; Unresponsive Call emergency services immediately and give naloxone if available — it reverses opioid overdoses.

How addictive is it?

Multiple UK deaths 2014–2015 (detected alongside etizolam and other NPS) Dependence can develop with regular use.

🔗Sources & further reading

Facts on this page are compiled from these primary sources. External links open in a new tab.